There are many types of bags for children known in the art. Some of these are shown in FIGS. 4 through 8 in which FIGS. 4 and 5 represent a rucksack or knapsack to be carried on the back of a child; FIG. 7 represents a satchel or school bag also carried on the back; FIG. 8 illustrates a shoulder bag to be hung on a shoulder and FIG. 6 shows a bag to be carried either with a hand or on a shoulder. There are also handbags or pocketbooks and "pochettes" to be hung on a waist belt, through not shown in the drawings.
These bags are usually made through a manufacturing process including cutting and sewing fabrics of synthetic or natural fibers, or natural or artificial leather, and providing a metallic lock. Some bags are provided with zipper fasteners around the openings so as to improve aesthetic appearance and render them easily usable. In general, many of these bags are made of soft materials so that they can hardly support their tridimensional shapes by themselves. Though some of these handbags have improved stiffness by incorporating reinforcing members in the main bodies, there are few bags of the prior art which are found to be satisfactory in respect of structural strength and stiffness.
The main body in which articles are accommodated in the prior art bags generally has very simple and plain surface configurations which are remote from complicated tridimensional shapes having uneven and irregular contours of, for example, a face of an animal, and very few have designs closely resembling a real animal. So, some measures have been adopted, including attaching to the bags adhesive-backed paper on which pictures are painted, or printing pictures directly on the lids, so as to suit children's tastes and try to win their favor, but these are essentially plain and unsatisfactory deceptive tactics.
Moreover, the lids of the prior art bags serve merely to cover the openings and are not suited to form a reinforcing structure in combination with the main body of the bag.
Thus, children's bags of the prior art have many deficiencies as enumerated below:
(1) They are generally of simple and conventional design and lack uniqueness and variety. In view of materials and methods utilized heretofore for making children's bags, it is very difficult to manufacture bags of characters and/or complicated contours which are precisely defined. Selection of the design of a bag is thus restricted within narrow limits.
(2) As the lid of the prior-art bag can not constitute a dynamically rigid, box-like structure in combination with the main body of the bag, the bag is so unstable that, upon pressing from outside, articles accommodated therein are easily bent or fractured.
Since the bag of the prior art is unstable and easily deformable, an opening of the bag can be made only so large without reducing strength and stiffness of the bag. To achieve shape retentivity of the bag of the prior art necessitates special consideration as to the size of the bag, thickness and density of materials used to form the main body of the bag, and reinforcing materials to improve stiffness of the bag.
(3) Among the lids of children's bags of the prior art are those which are folded through an angle ranging from 180.degree. to 360.degree. to open. The lids of this type are degraded at regions frequently folded, or cracked and virtually fractured.
Another type of lid utilizes zipper fasteners which often bit into articles contained in the bag and, when used for long period of time, weaken at their fabric borders where sewn to the bag.
A further type of the lid of the prior-art bags for children includes metal detents attached to the top of the main body which are twisted for locking and opening the gab. Locking means of this type is not suited to large bags, and in addition, it is deformed and loosened by creeping after long use.